Mixing and Transport in the Surfzone
Abstract
The long-term goal of this project was a better understanding surfzone mixing and transport that would allow improved prediction of the fate of terrestrial runoff pollution and other substances (e.g., fine sediment, chemicals) sometimes present in very shallow water. The objectives were as follows: (1) participate in analysis of waves and currents observed (NCEX, 2003) near the onshore branch of a submarine canyon, (2) develop methods to measure breaking wave-driven mixing and transport in the natural surf zone, and (3) use field observations to test and calibrate numerical models for surfzone mixing and transport. Wave breaking occurs most of the time on most ocean beaches. Even the most sophisticated numerical models must parameterize the highly turbulent dynamics of wave breaking, and the ensuing cascade of momentum and energy to both large and small scales of motion. Sediment transport adds another layer of theoretical uncertainty to models for wave-driven changes in beach morphology. My general approach is to use field observations to test and calibrate the heuristic numerical models used to model wave-driven beach processes. All aspects of the work, from pre-experiment planning to publication of results, are highly collaborative with students, post docs, and other scientists. Waves and currents observed near the La Jolla and Scripps submarine canyons during the ONR/NSF supported Nearshore Canyon Experiment (NCEX) have been analyzed and interpreted. Methods to observe transport and mixing in the surfzone using water-following drifters and fluorescent dye have been developed. Ongoing work uses dye and drifters as proxies for pollutants, chemicals from ordnance, and other tracers of interest.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2008
- Accession Number
- ADA514597
Entities
People
- R. T. Guza
Organizations
- Scripps Institution of Oceanography